Practically all rotating machinery requires the use of bearings to support rotating shafts or rotors. Oftentimes, the operating life of a piece of rotating machinery is no longer than the operating life of the bearings which support or receive the thrust from main shafts, crank shafts, etc. Many factors contribute to the degradation of, and the shortening of the lift of the bearings, not the least of which are corrosion by machine-processed fluids and abrasive particulate matter.
The aforementioned problems of corrosion and abrasive wear on bearings is most noticeable in machinery employed for solid waste comminution. Comminution is the reduction of particle size of solid waste and is generally performed by shredding, crushing or pulverizing such type of material. The action of a modern comminutor is well described in a patent issued to Chambers, U.S. Pat. No. 4,046,324, dated Sept. 6, 1977, for a SOLID WASTE COMMINUTOR. Therein, Chambers describes and offers a typical apparatus for processing solid waste by communution.
Inherent in the use of any machine which works with a medium of very small particulate matter will be the problem of accelerated bearing wear. For example, in addition to the excessive bearing wear found in comminutors, is that found in cement or gravel mixers, fertilizer and resin agitators and the like. As mentioned above, the operational life of these types of machines may be no longer than the operational life of their bearings. It has also been noted, in the case of this type of machine, that although manufacturers have attempted to extend the life of the bearings, through the use of integral protection systems, such attempts have been frustrated not by the particulate size of abrasives, but rather by the combination of abrasives, and especially in the case of solid waste comminutors, the corrosive liquid waste materials which are being processed.
A comminutor, of the type described above, suffers regular break-down primarily because of the interaction of the bearing material with machine-processed liquids, which have a pH ranging between 4 and 5, and often lower. Such chemical corrosion generally begins the process of bearing destruction which is finally completed by abrasion caused by grit and sand inclusion in the sludge-like processed material. Owing to the origin of such abrasive particulates, due primarily to street run-off, laundry effluent, cleansers used in kitchens/cafeterias, etc., it is readily apparent that comminutor operators will have to live with the problem rather than eliminate it before it enters the waste processing phase. Since the basic problem, that is, the propensity for short operational bearing life in such machines, is a chronic one, it is necessary to extend bearing life by some other means.
It is therefore an object of this invention to develop means for prolonging the operational life of bearings which are used in the construction of the aforementioned rotating machinery.
It is also an object of this invention to provide means which will ensure greater seal integrity, thus eliminating leakage and contamination from and by solid waste comminutors.
It is a further object of this invention to provide bearing protector means of a type readily adaptable to the several types of rotating machinery.
It is yet another object of this invention to provide bearing protector means which can be readily and economically fabricated as well as replaced in conjunction with regular preventive maintenance programs.
Finally, it is an object of this invention to provide non-integral machine bearing protective means which do not require a high degree of construction precision.
The objects and advantages of the invention are set forth in part and may also be learned by practice with the invention; the same being readily recognized through the disclosure herein made by those familiar with the art.